SMTP for SigNoz alert notifications not working in self-hosted K8s

TL;DR

Fixed in v0.101.0, per maintainer Nageshbansal (details in SigNoz/signoz#8478). If you are on an older self-hosted release, the SMTP alert path is the thing that is broken, not your values.yaml: upgrade to v0.101.0 or newer first.

Steps

1. Issue SigNoz/signoz#7580 (closed, 20 comments): On a self-hosted SigNoz in Kubernetes, configuring SMTP for alert notifications does not work. The reporter set the documented variables (SIGNOZALERTMANAGERSIGNOZGLOBALSMTPSMARTHOST, FROM, AUTHUSERNAME, AUTHPASSWORD) via alertmanager additionalEnvs in the helm values, following the configuration docs, and mail still never went out.
2. Fixed in v0.101.0, per maintainer Nageshbansal (details in SigNoz/signoz#8478). If you are on an older self-hosted release, the SMTP alert path is the thing that is broken, not your values.yaml: upgrade to v0.101.0 or newer first. Then set the SIGNOZALERTMANAGERSIGNOZGLOBALSMTP__* variables as alertmanager additionalEnvs in your helm values (SMARTHOST as host:port, FROM address, AUTH USERNAME and PASSWORD) and the alertmanager picks them up for alert notifications.

When to use

You are seeing this: Issue SigNoz/signoz#7580 (closed, 20 comments): On a self-hosted SigNoz in Kubernetes, configuring SMTP for alert notifications does not work. Use this skill when you run into "SMTP for SigNoz alert notifications not working in self-hosted K8s".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

Versions mentioned in the source: v0.101.0. If you are on something much newer or older, the details may have shifted.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

In gh:SigNoz/signoz#7580 (SigNoz), the issue reported was: Issue SigNoz/signoz#7580 (closed, 20 comments): On a self-hosted SigNoz in Kubernetes, configuring SMTP for alert notifications does not work. The reporter set the documented variables (SIGNOZALERTMANAGERSIGNOZGLOBALSMTPSMARTHOST, FROM, AUTHUSERNAME, AUTHPASSWORD) via alertmanager additionalEnvs in the helm values, following the configuration docs, and mail still never went out. The verified resolution from the thread: Fixed in v0.101.0, per maintainer Nageshbansal (details in SigNoz/signoz#8478). If you are on an older self-hosted release, the SMTP alert path is the thing that is broken, not your values.yaml: upgrade to v0.101.0 or newer first. Then set the SIGNOZALERTMANAGERSIGNOZGLOBALSMTP__* variables as alertmanager additionalEnvs in your helm values (SMARTHOST as host:port, FROM address, AUTH USERNAME and PASSWORD) and the alertmanager picks them up for alert notifications. Source: mount the host path https at container path //github.com/SigNoz/signoz/issues/7580